SALT LAKE CITY — The discovery of missing controlled substances within the Unified Fire Authority has led to prescription fraud charges filed against an assistant chief in what likely is a separate case.

Marlon Jones, 48, was charged Friday with 14 counts of obtaining a prescription under false pretenses, a third-degree felony.

Jones was seeing three different physicians to receive pain medications, including hydrocodone, carisoprodol and zolpidem, which he said he took three times daily, according to charges filed in 3rd District Court.

The doctors were unaware Jones was consulting other physicians and receiving prescriptions from them between May 2012 and April 2013, charges state.

Jones is a 24-year veteran of the Unified Fire Authority and was recently promoted to assistant chief, putting him in charge of eight fire stations in southeast Salt Lake County. He has been placed on paid leave, and his access to the fire stations has been suspended.

Unified Fire Chief Michael Jensen said Jones' activity was discovered when two outside police departments were brought in to investigate discrepancies in UFA's stock of three controlled substances used to treat pain, seizures and to sedate patients.

"We're not sure if (the charges) are correlated with (the discrepancies)," Jensen said. "Law enforcement agencies and the district attorney have not found any causal link back and forth to one another, but it did come out of the investigation."

Jensen said maintaining public trust and providing the best possible patient care are paramount in the investigation. He said he hopes the public will keep in mind the "human tragedy" of his collegue's situation throughout the legal process.

"He is a beloved firefighter," Jensen said. "He has been a valuable member of the agency and was a great paramedic. We don't want those things to be lost, either."

UFA's medicine stock is reviewed daily, in addition to a review following every call medical personnel respond to, Jensen said.

While no specific information about the missing medicine is being released during the investigation, Jensen said the problem appears to have existed for only a short time and was discovered through normal agency procedure.

The drugs are all in liquid form, he said. The only pills kept on hand are aspirin for patients experiencing a heart attack.

In the meantime, procedures for locking up controlled substances and ambulances have been tightened, Jensen said. He also pointed out that fire stations are public buildings, often hosting tours and events for visiting groups, requiring extra vigilance.